Well, for what its worth, here's a link to a scan of the
decision.
From skimming it, it seems that "not enough" is not so much a "there is reasonable doubt in the study" kind of thing.
The court's opinion goes something like this. The data they had suggested that the Cheetah brings both advantages
and disadvantages to the user relative to a normal leg.
The study, however, was specified to measure only the part where he had the advantage. It proceeds to conclude, naturally, that the guy receives a massive advantage from Cheetah.
It is a case of biased sampling, so to speak.